Supraventricular tachycardia

What is supraventricular tachycardia?

Supraventricular tachycardia (SVT) is an abnormal heart rhythm that causes the heart to beat rapidly.  The heart can beat from 100 to 260 beats per minute during one of these episodes.  The most common forms of SVT are caused by the presence of an extra electrical pathway in the heart.  These extra electrical pathways can cause the creation of en electrical loop that then causes the heart to beat very rapidly.  Examples of this form of SVT would include AV Nodal Reentry Tachycardia (AVNRT) and AtrioVentricular Reentry Tachycardia (AVRT).  Another common cause of SVT occurs when a single focus in the top chambers of the heart begins to send out rapid signals that then cause the heart to beat rapidly.  A common cause of this type of SVT is atrial tachycardia.

What are the signs and symptoms of supraventricular tachycardia?

Patients with supraventricular tachycardia can experience a variety of symptoms including a sensation of a rapid and irregular heart rate, fatigue, lightheadedness, fainting, shortness of breath, or chest pain.  These symptoms can last from minutes to days.  Death is an extremely rare complication of SVT.

What triggers supraventricular tachycardia?

Episodes of supraventricular tachycardia can be triggered by abnormal electrolyte levels in the blood, abnormal thyroid levels, medications, exercise, or caffeine.  For many patents, they episodes occur spontaneously with no identifiable triggers.

How can supraventricular tachycardia be treated?

The treatment for supraventricular arrhythmias depends upon the frequency of episodes and the severity of the patient’s symptoms.  Those patients who have infrequent episodes with mild symptoms, we may not recommend any treatment.  For patients with frequent episodes or severe symptoms, we may offer treatment with medications such as beta blockers, calcium channel blockers, or antiarrhythmic medications.  Another treatment option is a curative procedure called an ablation.